Cine Meter for iOS: FAQ

I can't find Cine Meter in the App Store! Where is it?

Are you searching on an iPad running iOS 6? By default, the App Store app only shows iPad apps. Select the “iPhone Apps” tab at the top of the screen, and Cine Meter should appear.

How do I manually set exposure and white balance?

I’m sorry, there is no manual mode: iDevice cameras don't allow it. Instead you have to lock the auto-exposure and auto-white-balance settings while looking at something with the proper exposure and white balance, like a gray card. See How To for details.

How big is the spot meter's spot?

It depends on your iDevice camera’s angle of view. On my iPod touch 4G, it’s about 10º.

Can I change the size of the spot metering area?

No, sorry. It’s set by the camera in your iDevice, and it isn't adjustable.

Why doesn’t the light meter match my DSLR / handheld meter?

Cine Meter computes exposure based on the standard APEX equation, using the assumed EXIF values for K and N. Its default calibration matches my Spectra Pro IV and Gossen Starlite meters very closely. However, it may not match your meters:

Have you calibrated Cine Meter to your reference meter?
“A photographer with one light meter knows what his exposure is. A photographer with two light meters is never sure.” Once you’ve calibrated Cine Meter to your reference, it should track pretty closely... as long as both meters see exactly the same angle of view, under the same color temperature. Meters (both handheld ones and built-in camera meters) differ in their color sensitivities and metering patterns, and it’s not unusual for two meters to match perfectly under certain conditions and differ by as much as a stop under others.

Why no incident meter mode?

Incident readings require incident light sensors, which iDevices lack. Cine Meter uses the iDevice’s camera. Like any other camera, it's a reflected-light sensor.

In theory one could turn an iDevice camera into an incident sensor by mounting a spherical diffuser or photosphere — one of those ping-pong-ball-lookalike domes — in front of the camera, but that’s not something I can do in software alone. When the Luxi ships, I plan to support it with an incident mode; until then, Cine Meter is for reflected light only.

You can shoot an 18% gray card with Cine Meter to get the same result as an incident meter would give you (though you may want to open up 1/2 stop from the reflected reading to match your incident meter’s reading).

Where’s the lux/footcandle reading?

It can’t be done with a reflected meter; not properly. Lux and footcandles are measures of light illuminating an object, not the light reflected from it.

The folks making Pocket Light Meter found that people were improperly using the lux/fc readouts in an early version of their app to judge emergency lighting installations and for other life-safety applications, so they had to take those measurements out. Let’s not go there...

Why no histogram? Frame grab / screenshot? Vertical mode? Front camera? iPad-specific mode? ND filter selection? Shutter angle selection? A green trace for the luma-only ‘scopes? Aperture-priority metering?

This is only version 1. These are all things I plan to add in Version 2. (The price will go up when Version 2 comes out; buy Version 1 and you get Version 2 for free.)

Where is the Android version?

I haven’t written it yet! I hope to have Cine Meter for Android (“Gingerbread” 2.3 and up) in the Android Market / Google Play by late summer 2013 (I was originally hoping for May, but I keep getting paid gigs that take up my time). Stay tuned...

Why isn’t my question answered here?

Because I haven’t heard it yet, that's why. Ask me and I’ll see if I can answer it.